Wireless power transfer is becoming increasingly popular in portable electronic devices, such as mobile phones, computer tablets, etc. Such devices typically require long battery life and low battery weight. The ability to power an electronic device without the use of wires is an attractive solution for users of portable electronic devices. Wireless power transfer gives manufacturers an option for developing solutions to problems due to limited choices for power sources in consumer electronic devices.
Wireless power transfer capability can improve the user's charging experience. In a multiple device charging situation, for example, wireless power transfer may reduce overall cost (for both the user and the manufacturer) because conventional charging hardware such as power adapters and charging chords can be eliminated. There is flexibility in having different coil sizes and shapes on the transmitter and/or the receiver in terms of industrial design and support for a wide range of devices from mobile handheld devices to computer laptops.
Designs for portable electronic devices may include a metallic housing or casing to house the display screen and the electronics that comprise the electronic device. Metallic materials are a comment design choice for their aesthetic qualities and structural support. Metal, however, impedes electromagnetic radiation, thus impacting wireless communication. Accordingly, housing designs that include metallic back covers may include openings formed through metallic portions of the metallic back cover, or incorporate non-metallic portions. Likewise, metallic housings can reduce the effectiveness of wireless power transfer. Solutions may include making additional cutouts in the back cover or reducing the amount of metal in the back cover, which can impact the structure and aesthetic qualities of the electronic device.